: Yes, those types of phrases are very derogatory.
: All those types of phrases, whether about Mexicans, Chinese, Poles etc, put the speaker above everyone else and these other people are inferior.

: : : WGS

: : as to wether "chinese fire drill" is derogatory I don't know, but it is used to indicate a mad dash for the exits. This meaning comes from the fact that fireworks are of chinese origin and any open flame around them is dangerous.

Sitting in a McDonalds and my connectin got trashed as did my post:

Yes, those types of phrases are very derogatory.
All those types of phrases, whether about Mexicans, Chinese, Poles etc, put the speaker above everyone else and insinuate that these other people are inferior.